Răspuns:
AD^2 = AB^2 - BD^2 (T.PIT.)
AD^2 = 24 - BD^2
AD^2 = AC^2 - DC^2
AD^2 = 12 - DC^2
24 - BD^2 = 12 - DC^2
24 - 12 = BD^2 - DC^2
(BD + DC)(BD - DC) = 12
6(BD - DC) = 12
BD - DC = 2
BD + DC = 6
___________ +
2BD / = 8 => BD = 4 => DC = 2
AD^2 = 24 - 16
AD^2 = 8
AD = 2rad2
